This paper considers the problem of posing and answering hypothetical temporal queries to databases. The queries are hypothetical in the sense that we pose a query to a virtually updated database, and the query is answered on the basis of the initial, physical database and the list of transactions that virtually update the database. The queries are temporal in the sense that they refer to possi...

We define a family of qualitative spatio-temporal relations such as same-place-same-time and same-path-different-time, which describe the relative location of spatio-temporal objects within places or along paths. The relations in question are approximate, and this means that some of them are context-dependent. We explore the relationships between context, judgments that are made in certain cont...

There is a wide range of scientific application domains requiring sophisticated management of spatio-temporal data. However, existing database management systems offer very limited (if any at all) support for managing such data. Thus, it is left to the researchers themselves to repeatedly code this management into each application. Besides being a time consuming task, this process is bound to i...

By supporting the valid and transaction time dimensions, bitemporal databases represent reality more accurately than conventional databases. In this paper, we examine the issues involved in designing efficient access methods for bitemporal databases, and propose the partial-persistence and the double-tree methodologies. The partial-persistence methodology reduces bitemporal queries to partial p...

Location-based services (LBS) constitute an emerging application domain involving spatio-temporal databases. In this paper, i) we propose a classification of LBS, depending on whether the user (query object) and the data objects are moving or not and ii) we provide algorithms for the efficient support of real applications, for every class. We also survey recent work in query processing for the ...

Methods: We compiled the Global Index of Vegetation-Plot Databases (GIVD; http://www.givd.info), an Internet resource aimed at registering metadata on existing vegetation databases. For inclusion, databases need to (i) contain temporally and spatially explicit species co-occurrence data and (ii) be accessible to the scientific public. This paper summarizes structure and data quality of database...

Recent research in the area of temporal databases has proposed a number of query languages that vary in their expressive power and the semantics they provide to users. These query languages represent a spectrum of solutions to the tension between clean semantics and efficient evaluation. Often, these query languages are implemented by translating temporal queries into standard relational querie...

Existing methods for the management of multidimensional data typically do not scale well with an increased number of dimensions or require the unsupported augmentation of the kernel. However, the use of multidimensional data continues to grow in modern database applications, specifically in spatio-temporal databases. These systems produce vast volumes of multidimensional data, and as such, data...

In this paper we study the ramification problem in the setting of temporal databases. Standard solutions from the literature on reasoning about action are inadequate because they rely on the assumption that fluents persist, and because actions have effects on the next situation only. In this paper we provide a solution to the ramification problem based on an extension of the situation calculus ...

The timestamps of now-relative bitemporal databases are modeled as growing, shrinking, or rectangular regions. The shape of these regions makes it a challenge to design bitemporal operators that a) are consistent with the pointbased interpretation of a temporal database, b) preserve the identity of the argument timestamps, c) ensure locality, and d) perform efficiently. We identify the bitempor...